Combined Effects of UVR and Temperature on the Survival of Crab Larvae (Zoea I) from Patagonia: The Role of UV-Absorbing Compounds

The aim of our study was to assess the combined impact of UVR (280–400 nm) and temperature on the first larval stage (Zoea I) of three crab species from the Patagonian coast: Cyrtograpsus altimanus, C. angulatus, and Leucippa pentagona. We determined the survival response of newly hatched Zoea I after being exposed for 8–10 h under a solar simulator (Hönle SOL 1200) at 15 and 20 °C. There was no mortality due to Photosynthetic Active Radiation (PAR, 400–700 nm) or ultraviolet-A radiation (UV-A, 315–400 nm), and all the observed mortality was due to ultraviolet-B radiation (UV-B, 280–315 nm). The data of larval mortality relative to exposure time was best fit using a sigmoid curve. Based on this curve, a threshold (Th) and the lethal dose for 50% mortality (LD50) were determined for each species. Based on the Th and LD50, C. altimanus was found to be the most resistant species, while L. pentagona was found to be the most sensitive to UV-B. For both species of Cyrtograpsus, mortality was significantly lower at 20 °C than at 15 °C; however, no significant differences between the two temperature treatments were found in L. pentagona. Bioaccumulation of UV-absorbing compounds in the gonads and larvae of C. altimanus, and to a lesser extent in C. angulatus, might have contributed for counteracting the impact of UV-B. However, most of the resilience to UV-B observed with the increase in temperature might be due to an increase in metabolic activity caused by a repair mechanism mediated by enzymes

In situ impact of solar ultraviolet radiation on photosynthesis and DNA in temperate marine phytoplankton

In situ experiments were conducted at various depths in the water column to determine the impact of solar UV radiation (280 to 400 nm) upon photosynthesis and DNA of natural phytoplankton assemblages from mid-latitudes of Patagonia (Bahia Bustamante, Chubut, Argentina; 45 degreesS, 66.5 degreesW). The effects of UV radiation were significant at the surface; however, the impact decreased rapidly with depth: at 3 m there was no measurable DNA damage accumulation, whereas at 6 m photosynthetic inhibition was almost zero. UV-A radiation (315 to 400 nm) was mostly responsible for photosynthetic inhibition, while UV-B radiation (280 to 315 nm) had a lesser effect on this process. However, UV-B radiation was very effective in damaging the DNA through the formation of cyclobutane pyrimidine dimers (CPDs) in surface waters. The high initial CPD level found in the natural phytoplankton assemblage decreased when samples were incubated at 3 or 6 m, indicating that at these depths repair, dilution or disappearance of damage occurred. Phytoplankton assemblages were dominated by cells less than 2 mum in effective diameter; this cell size category seems to be more resistant to photosynthetic inhibition, but vulnerable to CPD accumulation, as compared with larger eukaryotic phytoplankters (i.e., Phaeodactylum sp.)

Heterogeneity within AML with CEBPA mutations; only CEBPA double mutations, but not single CEBPA mutations are associated with favourable prognosis

CCAAT/enhancer binding protein alpha (CEBPA) mutations in AML are associated with favourable prognosis and are divided into N- and C-terminal mutations. The majority of AML patients have both types of mutations. We assessed the prognostic significance of single (n=7) and double (n=12) CEBPA mutations among 224 AML patients. Double CEBPA mutations conferred a decisively favourable overall (P=0.006) and disease-free survival (P=0.013). However, clinical outcome of patients with single CEBPA mutations was not different from CEBPA wild-type patients. In a multivariable analysis, only double – but not single – CEBPA mutations were identified as independent prognostic factors. These findings indicate heterogeneity within AML patients with CEBPA mutations

Interdisciplinary evidence-based recommendations for the follow-up of testicular cancer patients: a joint effort

Detailed recommendations for the treatment of testicular cancer exist and due to the stringent application of the standard therapies, most patients can nowadays be cured. Moreover in the treatment of early stage disease, active surveillance is now a cornerstone of treatment. Hence there is a clear need for recommendations regarding the long term follow-up of these young patients. These have to be safe, feasible and the intensity of procedures have to reflect the known risk of recurrence. Different proposals have been published but they differ widely especially in terms of frequency and modality of imaging. In the last few years, new evidence has become available regarding the relapse pattern of different disease stages of testicular cancer, the use of imaging in follow-up and the risks of excessive radiation due to imaging, in particular with CT scans. In this article, an interdisciplinary, multinational working group has reviewed the evidence and based on this has formulated practical recommendations for the follow-up of patients with testicular cancer

Is Computed-Tomography-Based Body Composition a Reliable Predictor of Chemotherapy-Related Toxicity in Pancreatic Cancer Patients?

BACKGROUND Malnutrition, loss of weight and of skeletal muscle mass are frequent in pancreatic cancer patients, a majority of which will undergo chemotherapy over the course of their disease. Available data suggest a negative prognostic role of these changes in body composition on disease outcomes; however, it is unclear whether tolerance to chemotherapeutic treatment is similarly and/or negatively affected. We aimed to explore this association by retrospectively assessing changes in body composition and chemotherapy-related toxicity in a cohort of advanced pancreatic cancer patients. METHODS Body composition was evaluated through clinical parameters and through radiological assessment of muscle mass, skeletal muscle area, skeletal muscle index and skeletal muscle density; and an assessment of fat distribution by subcutaneous adipose tissue and visceral adipose tissue. We performed descriptive statistics, pre/post chemotherapy comparisons and uni- and multivariate analyses to assess the relation between changes in body composition and toxicity. RESULTS Toxicity risk increased with an increase of skeletal muscle index (OR: 1.03) and body mass index (OR: 1.07), whereas it decreased with an increase in skeletal muscle density (OR: 0.96). Multivariate analyses confirmed a reduction in the risk of toxicity only with an increase in skeletal muscle density (OR: 0.96). CONCLUSIONS This study suggests that the retrospective analysis of changes in body composition is unlikely to be useful to predict toxicity to gemcitabine-nab-paclitaxel

The effects of dilution and mixed layer depth on deliberate ocean iron fertilization : 1-D simulations of the southern ocean iron experiment (SOFeX)

Author Posting. © Elsevier B.V., 2007. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Journal of Marine Systems 71 (2008): 112-130, doi:10.1016/j.jmarsys.2007.07.002.To better understand the role of iron in driving marine ecosystems, the Southern Ocean Iron Experiment (SOFeX) fertilized two surface water patches with iron north and south of the Antarctic Polar Front Zone (APFZ). Using 1-D coupled biological-physical simulations, we examine the biogeochemical dynamics that occurred both inside and outside of the fertilized patches during and shortly after the SOFeX field campaign. We focus, in particular, on three main issues governing the biological response to deliberate iron fertilization: the interaction among phytoplankton, light, macro-nutrient and iron limitation; dilution and lateral mixing between the fertilized patch and external, unfertilized waters; and the effect of varying mixed layer depth on the light field. At the patch south of the APFZ, sensitivity simulations with no dilution results in the maximum bloom magnitude, whereas dilution with external water extends the development of the north patch bloom by relieving silicon limitation. In model sensitivity studies for both sites, maximum chlorophyll concentration and dissolved inorganic carbon depletion inside the fertilized patches are inversely related to mixed layer depth, similar to the patterns observed across a number of iron fertilization field experiments. Our results suggest that Southern Ocean phytoplankton blooms resulting from natural or deliberate iron fertilization will tend to become iron-light co-limited unless the mixed layer depth is quite shallow.This work was supported by NASA grant NAG5-12520 from the NASA Ocean Biogeochemistry Program

Critical review of the use of erythropoietin in the treatment of anaemia during therapy for chronic hepatitis C

SUMMARY. Combined pegylated interferon (PegIFN) and ribavirin represents the standard therapy for patients with chronic hepatitis C (CHC), which allows for sustained viral response (SVR) in up to 90% of patients depending on certain viral and host factors. Clinical studies have demonstrated the importance of adherence to therapy, that is, the ability of patients to tolerate and sustain a fully dosed therapy regimen. Adherence is markedly impaired by treatment-related adverse effects. In particular, haemolytic anaemia often requires dose reduction or termination of ribavirin treatment, which compromises treatment efficacy. Recent evidence points to a beneficial role of recombinant erythropoietin (EPO) in alleviating ribavirin-induced anaemia thereby improving quality of life, enabling higher ribavirin dosage and consequently improving SVR. However, no general consensus exists regarding the use of EPO for specific indications: its optimal dosing, treatment benefits and potential risks or cost efficiency. The Swiss Association for the Study of the Liver (SASL) has therefore organized an expert meeting to critically review and discuss the current evidence and to phrase recommendations for clinical practice. A consensus was reached recommending the use of EPO for patients infected with viral genotype 1 developing significant anaemia below 100 g/L haemoglobin and a haematocrit of <30% during standard therapy to improve quality of life and sustain optimal ribavirin dose. However, the evidence supporting its use in patients with pre-existing anaemia, non-1 viral genotypes, a former relapse or nonresponse, liver transplant recipients and cardiovascular or pulmonary disease is considered insufficient

Grazing Rates of Calanus finmarchicus on Thalassiosira weissflogii Cultured under Different Levels of Ultraviolet Radiation

UVB alters photosynthetic rate, fatty acid profiles and morphological characteristics of phytoplankton. Copepods, important grazers of primary production, select algal cells based upon their size, morphological traits, nutritional status, and motility. We investigated the grazing rates of the copepod Calanus finmarchicus on the diatom Thalassiosira weissflogii cultured under 3 levels of ultraviolet radiation (UVR): photosynthetically active radiation (PAR) only (4 kJ-m−2/day), and PAR supplemented with UVR radiation at two intensities (24 kJ-m−2/day and 48 kJ-m−2/day). There was no significant difference in grazing rates between the PAR only treatment and the lower UVR treatment. However, grazing rates were significantly (∼66%) higher for copepods feeding on cells treated with the higher level of UVR. These results suggest that a short-term increase in UVR exposure results in a significant increase in the grazing rate of copepods and, thereby, potentially alters the flow rate of organic matter through this component of the ecosystem

Anti-photoaging and Photoprotective Compounds Derived from Marine Organisms

Marine organisms form a prominent component of the oceanic population, which significantly contribute in the production of cosmeceutical and pharmaceutical molecules with biologically efficient moieties. In addition to the molecules of various biological activities like anti-bacterial, anti-cancerous, anti-inflammatory and anti-oxidative etc., these organisms also produce potential photoprotective or anti-photoaging agents, which are attracting present day researchers. Continuous exposure to UV irradiation (both UV-A and UV-B) leads to the skin cancer and other photoaging complications, which are typically mediated by the reactive oxygen species (ROS), generated in the oxidative pathways. Many of the anti-oxidative and anti-photoaging compounds have been identified previously, which work efficiently against photodamage of the skin. Recently, marine originated photoprotective or anti-photoaging behavior was observed in the methanol extracts of Corallina pilulifera (CPM). These extracts were found to exert potent antioxidant activity and protective effect on UV-A-induced oxidative stress in human dermal fibroblast (HDF) cells by protecting DNA and also by inhibiting matrix metalloproteinases (MMPs), a key component in photoaging of the skin due to exposure to UV-A. The present review depicts various other photoprotective compounds from algae and other marine sources for further elaborative research and their probable use in cosmeceutical and pharmaceutical industries